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arXiv · 2407.04469

Muon spectroscopy investigation of anomalous dynamic magnetism in NiI$_2$

T. L. Breeze·B. M. Huddart·A. Hernández-Melián·N. P. Bentley·D. A. Mayoh·G. D. A. Wood·G. Balakrishnan·J. Wilkinson·F. L. Pratt·T. J. Hicken·S. J. Clark·T. Lancaster
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Abstract

We present the results of muon-spin relaxation ($\mu^{+}$SR) measurements of the van der Waals magnet NiI$_2$, which probe magnetic phase transitions at $T_{\mathrm{N1}}=73$~K and $T_{\mathrm{N2}}=60$~K. Supporting density functional theory (DFT) calculations allow the determination of a single muon stopping site whose magnetic environment is consistent with the proposed ground-state magnetic structure. $\mu^{+}$SR measurements of the dynamics reveal behavior consistent with spin-wave excitations below $T_{\mathrm{N2}}$. In the region $T_{\mathrm{N2}}<T<T_{\mathrm{N1}}$ the character of the dynamics changes qualitatively, resulting in an unusual region of temperature-independent fluctuations.

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T. L. Breeze, B. M. Huddart, A. Hernández-Melián, N. P. Bentley, D. A. Mayoh, G. D. A. Wood, G. Balakrishnan, J. Wilkinson, F. L. Pratt, T. J. Hicken, S. J. Clark, T. Lancaster. 2024-07-05. Muon spectroscopy investigation of anomalous dynamic magnetism in NiI$_2$. https://arxiv.org/abs/2407.04469

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